Periodic limb movement disorder in children: A systematic review

This systematic review evaluates the scientific literature on pediatric periodic limb movement disorder (PLMD), adhering to PRISMA guidelines and utilizing PICOS criteria. The search across PubMed, EMBASE, and Scopus yielded 331 articles, with 17 meeting inclusion criteria. Diagnostic criteria evolved, with polysomnography and PLMS index ≥5 required since 2003. Also, PLMD diagnosis mandates clinical consequences like insomnia, hypersomnia, and fatigue, excluding comorbidities causing sleep disruption. Prevalence in children is low (0.3%), emphasizing the need for meticulous investigation. Comorbidities, particularly the bidirectional relationship with ADHD, were explored. Challenges in diagnosis and understanding arise from overlapping conditions such as sleep disordered breathing, psychotropic medication, and criteria non-adherence. Despite generally good study quality, weaknesses include sample size justification and biases. The periodic leg movement index shows high sensitivity but low specificity, underscoring strict diagnostic criteria adherence. Diverse metrics for symptoms necessitate standardized approaches. Family history of RLS in children with PLMD suggests unexplored aspects. Treatment, mainly iron supplementation, lacks standardized assessment metrics. The review emphasizes diagnostic and treatment challenges, recommending unbiased studies with precise techniques. Comprehensive research, quantifying PLMS and objectively assessing sleep parameters, is crucial for advancing understanding in pediatric PLMD. PROSPERO REGISTRATION NUMBER: CRD42021251406.

Neurocognitive Effects of Sleep Disruption in Children and Adolescents

A main childhood task is learning. In this task, the role of sleep is increasingly demonstrated. Although most literature examining this role focuses on preadolescence and middle adolescence, some studies apply napping designs in preschoolers. Studies overall conclude that without proper sleep a child's cognitive abilities suffer, but questions on how and to what extent linger. Observational studies show the hazards of potential confounders such as an individual's resilience to poor sleep as well as developmental risk factors (eg, disorders, stressors). A better understanding of cognitive sleep neuroscience may have a big impact on pediatric sleep research and clinical applications.

Sleep and the Social Profiles of Individuals With Rett Syndrome

BACKGROUND

This study investigates the distinctive social behaviors observed in individuals with Rett syndrome (RTT), characterized by the loss of spoken language, impaired eye gaze communication, gait abnormalities, and sleep issues. The research aims to identify social profiles in RTT and explore their correlation with sleep, sleep-disordered breathing (SDB), and daytime sleepiness.

METHODS

Standard overnight sleep macrostructure and respiratory parameters were assessed. Extracting 25 social-related items and one for daytime sleepiness from the Rett Syndrome Behavioral Questionnaire, factor analysis was applied to establish latent social profiles. These profiles were then correlated with sleep parameters. The nonparametric Mann-Whitney U test compared social profiles based on the presence of SDB (defined by an apnea-hypopnea index greater than one per hour) and daytime sleepiness.

RESULTS

The study involved 12 female subjects with confirmed RTT diagnoses and MECP2 mutations, aged 8.54 ± 5.30 years. The Rett Syndrome Behavioral Questionnaire revealed a total average score of 25.83 ± 12.34, indicating varying degrees of social impairments. Comprising 25 social-related items, factor analysis yielded four social profiles: "interactive motricity," "mood change," "anxiety/agitation," and "gazing." Longer sleep onset latency correlated with increased socio-behavioral impairments, particularly in interactive motricity reduction. Conversely, higher rapid eye movement sleep was associated with fewer interactive socio-motor behaviors. No significant differences in social profiles were found concerning the presence of SDB or daytime sleepiness.

CONCLUSIONS

The findings suggest four distinct social profiles in RTT individuals, hinting at shared disrupted circuits between sensorimotor functioning and sleep-related neuronal pathways. Despite the absence of differences in SDB or daytime sleepiness, the study highlights the relationship between sleep parameters, such as sleep onset latency and rapid eye movement sleep, and socio-behavioral outcomes in RTT with MECP2 mutations.

Assessing psychometric properties and measurement invariance of the Sleep Quality Questionnaire among healthcare students

OBJECTIVE

The sleep of healthcare students is worth discovering. Mental health and self-rated health are thought to be associated with sleep quality. As such, valid instruments to assess sleep quality in healthcare students are crucial and irreplaceable. This study aimed to investigate the measurement properties of the Sleep Quality Questionnaire (SQQ) for Chinese healthcare students.

METHODS

Two longitudinal assessments were undertaken among healthcare students, with a total of 595, between December 2020 and January 2021. Measures include the Chinese version of the SQQ, Patient Health Questionnaire-4 (PHQ-4), Self-Rated Health Questionnaire (SRHQ), and sociodemographic questionnaire. Structural validity through confirmatory factor analysis (CFA) was conducted to examine factor structure of the SQQ. T-tests and ANOVAs were used to examine sociodemographic differences in sleep quality scores. Multi Group CFA and longitudinal CFA were respectively used to assess cross-sectional invariance and longitudinal invariance across two-time interval, i.e., cross-cultural validity. Construct validity, internal consistency, and test-retest reliability were correspondingly examined via Spearman correlation, Cronbach's alpha and McDonald's omega, and intraclass correlation coefficient. Multiple linear regression analysis was performed to examine incremental validity of the SQQ based on the PHQ-4 and SRHQ as indicators of the criterion variables.

RESULTS

CFA results suggested that the two-factor model of the SQQ-9 (item 2 excluded) had the best fit. The SQQ-9 scores differed significantly by age, grade, academic stage, hobby, stress coping strategy, anxiety, depression, and self-rated health subgroups. Measurement invariance was supported in terms of aforesaid subgroups and across two time intervals. In correlation and regression analyses, anxiety, depression, and self-rated health were moderately strong predictors of sleep quality. The SQQ-9 had good internal consistency and test-retest reliability.

CONCLUSION

Good measurement properties suggest that the SQQ is a promising and practical measurement instrument for assessing sleep quality of Chinese healthcare students.

Review of the role of the endogenous opioid and melanocortin systems in the restless legs syndrome

Restless legs syndrome (RLS) is responsive to opioid, dopaminergic and iron-based treatments. Receptor blocker studies in RLS patients suggest that the therapeutic efficacy of opioids is specific to the opioid receptor and mediated indirectly through the dopaminergic system. An RLS autopsy study reveals decreases in endogenous opioids, β-endorphin and perhaps Met-enkephalin in the thalamus of RLS patients. A total opioid receptor knock-out (mu, delta and kappa) and a mu-opioid receptor knock-out mouse model of RLS show circadian motor changes akin to RLS and, although both models show sensory changes, the mu-opioid receptor knock mouse shows circadian sensory changes closest to those seen in idiopathic RLS. Both models show changes in striatal dopamine, anaemia and low serum iron. However, only in the total receptor knock-out mouse do we see the decreases in serum ferritin that are normally found in RLS. There are also decreases in serum iron when wild-type mice are administered a mu-opioid receptor blocker. In addition, the mu-opioid receptor knock-out mouse also shows increases in striatal zinc paralleling similar changes in RLS. Adrenocorticotropic hormone and α-melanocyte stimulating hormone are derived from pro-opiomelanocortin as is β-endorphin. However, they cause RLS-like symptoms and periodic limb movements when injected intraventricularly into rats. These results collectively suggest that an endogenous opioid deficiency is pathogenetic to RLS and that an altered melanocortin system may be causal to RLS as well.

Sleep quality and subjective well-being in healthcare students: examining the role of anxiety and depression

Objective

Sleep issues, negative emotions, and health conditions are commonly co-occurring, whereas their associations among healthcare students have yet to be elucidated. This study aimed to examine whether anxiety and depression mediate the relationship between sleep quality and subjective well-being in healthcare students.

Methods

A cross-sectional survey was conducted among Chinese healthcare students (N = 348). A battery of paper-and-pencil questionnaires-the Sleep Quality Questionnaire (SQQ), World Health Organization-Five Well-Being Index (WHO-5), and Patient Health Questionnaire-4 (PHQ-4) were applied. Descriptive analysis with means (standard deviations) and counts (proportions), Spearman correlation analysis between the SQQ, WHO-5, and PHQ-4, and mediation analysis via structural equation models were performed.

Results

Correlation analysis revealed statistically significant associations between sleep quality, anxiety and depression, and well-being among healthcare students. Mediation analysis identified that poor sleep quality produced relatively low levels of self-reported well-being, which were entirely attributable to anxiety and depression.

Conclusion

Sleep quality was associated with subjective well-being, and this interrelationship was fully mediated by anxiety and depression. Interventions aimed at promoting sleep quality of healthcare students may contribute to promoting their well-being by reducing anxiety and depression.

The interaction between stress and sleep disorders among foreign medical students in Georgia

OBJECTIVES

This study aimed to: a. Investigate daytime sleepiness, stress, and pre-sleep arousal prevalence among foreign medical students in Georgia. b. Explore gender-based associations between sleep and stress parameters.

METHODS

Mental health was assessed in 207 foreign medical students in Georgia using the Epworth Sleepiness Scale (ESS), Pre-Sleep Arousal Scale (PSAS), and Student-Life Stress Inventory (SLSI).

RESULTS

Most participants reported elevated stress levels and excessive daytime sleepiness (EDS). EDS affected 25.1% of students, with slightly higher prevalence in males. PSAS was prevalent in 97.1% of students. Stress was widely reported, with 78% experiencing it, with a higher prevalence in females. Significant correlations were observed between sleepiness and arousal, including somatic (r = 0.41) and total scores (r = 0.28). Sleepiness was also linked to stressors like pressure, changes, self-imposed stress, and overall self-evaluation stress (r = 0.45). Strong correlations existed between ESS, Total PSAS, and overall self-evaluation SLSI scores for both genders. Gender differences were observed in the associations with Cohen's d within the small to moderate size. Men showed significant associations between ESS and stressors: conflict, pressure, chances, all stress reaction categories, and total SLSI scores (p < 0.001). In women, ESS correlated significantly only with overall self-evaluation (p < 0.001). Excessive daytime sleepiness, especially with somatic and total PSAS, predicted total SLSI scores for the entire sample and both genders, with stronger predictive values for total PSAS.

CONCLUSION

The study reveals a high prevalence of clinical sleepiness and its significant correlation with pre-sleep arousal and stress among foreign medical students, with females experiencing more difficulties than males.

Development and validation of the narcolepsy severity scale in school aged children

OBJECTIVE

To develop and psychometrically test the pediatric narcolepsy severity scale (P-NSS) for pediatric with narcolepsy type 1 (NT1).

METHODS

Item pool was formed based on literature review, clinical judgement of the expert panel and input of the narcoleptic patients and their parents. Psychometric properties were evaluated after applying the P-NSS in a sample of 200 patients (8-18 years age) with narcolepsy. Analyses included item analysis, validity analysis and reliability analysis.

RESULTS

P-NSS consisted four factors with a total of 17 items. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) revealed four distinct and theoretically coherent factors, explaining 63.4% of the total variance. The fitting results of the CFA model were χ2/dƒ = 2.235, GFI = 0.876, AGFI = 0.822, RMSEA = 0.079, TLI = 0.908, CFI = 0.927. P-NSS score is correlated with Pediatric Daytime Sleepiness Scale (r = 0.512, P < 0.01), Epworth Sleepiness Scale for Children and Adolescents (r = 0.355, P < 0.01) and Narcolepsy quality-of-life instrument with 21 questions (r = -0.512, P < 0.01). Cronbach's α coefficient for P-NSS and four dimensions were from 0.732 to 0.915. The split-half reliability was 0.882 (P < 0.01).

CONCLUSION

P-NSS is proved to be a reliable and valid measure for Chinese children with NT1. It may serve in China as a valuable and easily accessible outcome measure for using in narcolepsy trials, the clinic with improved responsiveness and long term follow-up.

Developing a serious game for gaze stability rehabilitation in children with vestibular hypofunction

BACKGROUND

Children with vestibular hypofunction (VH) may have gaze instability, balance disorders, and delayed postural-motor development. Gaze stabilization exercises (GSE) are designed to improve dynamic visual acuity (DVA). We aimed to assess the acceptability of a serious game prototype called Kid Gaze Rehab (KGR) designed to implement GSE training in children with VH, combined with traditional vestibular rehabilitation. Effects on DVA and motor performance were also analyzed.

METHODS

Twelve children (6 to 9 years old) were included. Sessions were held at the hospital twice a week, for 5 weeks. An adapted French version of The Child Simulator Sickness Questionnaire (SSQ) and the Face Scale Pain-Revised (FPS-R) were used to assess pain in the cervical region and undesirable side effects after each session. Vestibular and motor function parameters (active and passive DVA and Movement Assessment Battery for Children-Second Edition, MABC-2) were assessed before and after the training.

RESULTS

All children included completed the 10 sessions. The FPS-R visual analog scale and SSQ showed good cervical tolerance and no oculomotor or vegetative adverse effects nor spatial disorientation. After training, active DVA scores were significantly improved for the right, left, and up directions (p < 0.05). Passive DVA scores were significantly improved for the left and down directions (p < 0.01 and p < 0.05, respectively). MABC-2 scores were improved in the balance and ball skill sections (p < 0.05).

CONCLUSION

An innovative pediatric training method, the use of a dedicated serious game for gaze stabilization was well-tolerated as a complement to conventional vestibular rehabilitation in children with VH. Moreover, both DVA and motor performance were found to improve in the study sample. Although replication studies are still needed, serious game-based training in children with VH could represent a promising rehabilitation approach for years to come.

TRIAL REGISTRATION

The study was conducted in accordance with the Declaration of Helsinki and approved by an Institutional Review Board (local ethics committee, CPP Sud-Est IV, ID 2013-799). The study protocol was registered on ClinicalTrials.gov (NCT04353115).

The Ponto-Geniculo-Occipital (PGO) Waves in Dreaming: An Overview

Rapid eye movement (REM) sleep is the main sleep correlate of dreaming. Ponto-geniculo-occipital (PGO) waves are a signature of REM sleep. They represent the physiological mechanism of REM sleep that specifically limits the processing of external information. PGO waves look just like a message sent from the pons to the lateral geniculate nucleus of the visual thalamus, the occipital cortex, and other areas of the brain. The dedicated visual pathway of PGO waves can be interpreted by the brain as visual information, leading to the visual hallucinosis of dreams. PGO waves are considered to be both a reflection of REM sleep brain activity and causal to dreams due to their stimulation of the cortex. In this review, we summarize the role of PGO waves in potential neural circuits of two major theories, i.e., (1) dreams are generated by the activation of neural activity in the brainstem; (2) PGO waves signaling to the cortex. In addition, the potential physiological functions during REM sleep dreams, such as memory consolidation, unlearning, and brain development and plasticity and mood regulation, are discussed. It is hoped that our review will support and encourage research into the phenomenon of human PGO waves and their possible functions in dreaming.

Validation of the Chinese version of the Perceived Stress Scale-10 integrating exploratory graph analysis and confirmatory factor analysis

OBJECTIVE

The study aimed to initially assess the measurement properties of the 10-item simplified Chinese version of the Perceived Stress Scale (PSS-C-10) and as a first, assess a longitudinal measurement invariance (LMI).

METHODS

A longitudinal survey was conducted with a convenient sample of healthcare students using the PSS-C-10. We assessed the PSS-C-10 mainly using composite analytical approaches, including exploratory graph analysis (EGA) and confirmatory factor analysis (CFA) to suggest the best-fit factor structure and assess measurement invariance.

RESULTS

The EGA identified a two-factor structural solution with an accuracy of 98.6% at baseline and 100% at a 7-day follow-up. The CFA subsequently confirmed this structure, with a comparative fit index of 0.963 at baseline and 0.987 at follow-up, Tucker-Lewis index of 0.951 at baseline and 0.982 at follow-up, and root mean square error of approximation of 0.111 at baseline and 0.089 at follow-up. The LMI was supported by the goodness-of-fit indices, and their changes fell within the recommended cut-off range. Additionally, Cronbach's alpha (0.885 at baseline and 0.904 at follow-up), McDonald's omega (0.885 at baseline and 0.902 at follow-up), and an ICC value of 0.816 for 7 days demonstrated the robust reliability of the PSS-C-10.

CONCLUSION

The PSS-C-10 exhibited a stable two-factor structure with promising LMI and measurement properties.

Hyperactivity in patients with narcolepsy and idiopathic hypersomnia: an exploratory study

Introduction

Patients with either Idiopathic Hypersomnia or Narcolepsy demonstrate excessive daytime somnolence (EDS) with resultant inattention mimicking Attention Deficit Hyperactivity Disorder (ADHD). Patients with ADHD also often express sleep problems including EDS. Thus, patients with ADHD and patients with idiopathic hypersomnia or narcolepsy may share inattention and daytime drowsiness as common features. However, it is not known whether EDS patients with idiopathic hypersomnia or narcolepsy also have increased movement (hyperactivity) like ADHD patients, the determination of which is the purpose of this study.

Methods

We studied 12 patients (7 Narcolepsy type 2 and 5 Idiopathic Hypersomnia) with EDS as shown by Multiple Sleep Latency Test which served as the gold standard for entry into the study. Twelve subjects without symptoms of EDS served as the control group. None of the participants had a previous history of ADHD. Each participant underwent a one-hour session laying at 45 degrees with surveys about the need to move and actigraphy as an objective measure of movement.

Results

Sleep-disordered patients with EDS reported more symptoms of inattention and hyperactivity on the ADHD Self-Report Scale. At each of the time points patients with EDS had a clear trend to express the need to move more than controls on the Suggested Immobilization Test (SIT). For the total 60 minutes, a large effect size for the need to move during the SIT test was found between patients and controls (Cohen's d = 0.61, p=0.01). Patients with EDS did not express a need to move more to combat drowsiness than controls, nor did actigraphy show any difference in objective movement between patients and controls during the SIT.

Conclusion

Patients with EDS express inattention and a need to move more than controls. However, hyperactivity was not verified by objective measurement, nor did the EDS patients express a need to move to combat drowsiness more than controls. Thus, a hypothesis to be further tested, is whether narcolepsy and idiopathic hypersomnia may be more a model of the inattentive form of ADHD rather than the combined or inattentive/hyperactive form of ADHD. Further studies are needed to explore the relationship between EDS and hyperactivity.

Polysomnographic study in pediatric neurofibromatosis type 1

Background

Neurofibromatosis type 1 (NF1) is a genetic disease that alters neurodevelopment. We aimed to analyze the sleep macrostructure of a sample of children affected by NF1 without neurocognitive co-morbidities and MRI reports of unidentified bright objects (UBOs).

Methods

A 100 pre-pubertal children participated in the cross-sectional study: 50 subjects were children diagnosed with NF1 and 50 subjects were typically developing healthy children (TDC). All participants underwent polysomnographic evaluation through which conventional sleep parameters were collected: Total sleep time (TST), Sleep latency (SOL), first REM latency (FRL), number of stage shifts/h (SS/h), number of awakenings/h (AWN/h), wake after sleep onset (WASO%), sleep efficiency percentage (SE%), percentage of sleep time spent in sleep stages 1 (N1%) and 2 (N2%), slow-wave sleep (N3%), and REM sleep (REM%). Additionally, nocturnal respiratory events such as apnea/hypopnea index (AHI), oxygen desaturation index (ODI), and periodic limb movement index (PLMI) were recorded.

Results

Neurofibromatosis type 1 children showed a reduction in sleep duration parameters (TST; p < 0.001), sleep efficiency (SE%; p < 0.001), and stage N2% (p < 0.001). Moreover, the number of awakenings per hour (AWN/h), wake after sleep onset (WASO%), and respiratory events such as AHI, ODI, and PLMI resulted higher in NF1 vs. TDC children.

Conclusion

The data showed that the sleep macrostructure differs between NF1 and TDC children. These findings suggest that the evaluation of sleep may provide useful support in corroborating the diagnosis and offers additional therapeutic management perspectives in NF1 and genetic neurodevelopmental disorders in general.

The RU_SATED as a measure of sleep health: cross-cultural adaptation and validation in Chinese healthcare students

BACKGROUND

The RU_SATED scale is a multidimensional instrument measuring sleep health, consisting of Regularity, Satisfaction, Alertness, Timing, Efficiency, Duration dimensions. We adapted and validated the Chinese RU_SATED (RU_SATED-C) scale.

METHODS

The RU_SATED-C scale was developed through a formal linguistic validation process and was validated in an observational longitudinal survey design. Healthcare students completed the RU_SATED scale, Sleep Quality Questionnaire, and Patient Health Questionnaire-4 among two sites of Hangzhou and Ningbo, China. Psychometric assessments included structural validity, longitudinal measurement invariance, convergent and divergent validity, internal consistency, and test-retest reliability.

RESULTS

A total of 911 healthcare students completed the RU_SATED-C scale at baseline (Time 1, T1) and follow-up (Time 2, T2) with an average time interval of 7 days + 5.37 h. Confirmatory factor analysis (CFA) confirmed a single-factor model and resulted in an acceptable model fit. The two-factor model previously found in the Japanese version fit better than the one-factor model, whereas the one-factor model fit had a better fit than the two-factor model found in the English version. Longitudinal CFA resulted in negligible changes in fit indices for four forms of increasingly restrictive models and supported that a single-factor model was equivalent over time. The data also endorsed longitudinal measurement invariance among the two-factor models found in the English and Japanese samples. The RU_SATED-C scale total score displayed a moderately strong negative correlation with sleep quality; however, negligible associations were observed with anxiety and depression. Ordinal Cronbach's alpha and Ordinal McDonald's omega at T1 and T2 ranged from suboptimal to acceptable. The RU_SATED-C scale and all items were significantly correlated across time intervals.

CONCLUSION

The RU_SATED-C scale is an easy-to-use instrument with potentially valid data for the measurement of multidimensional sleep health. Use of the RU_SATED-C scale can help raise awareness of sleep health and could pave the way for important efforts to promote healthy sleep.

Personality Characteristics of Children and Adolescents with Anxiety Disorder from a Maternal Perspective: A Brief Report

The present study assessed the personality characteristics of children and adolescents with anxiety disorder from a maternal perspective. A total of 48 children and adolescents aged between 8 and 17 years participated in this study, which was organized as follows: a clinical group (24 children and adolescents with anxiety disorders and their respective mothers) and a control group (24 children and adolescents without psychiatric diagnosis and their mothers). The participants were submitted to the WASI, CBCL, MASC-2, and EPQ-J tests and their mothers to the SRQ-20 and PIC-2 tests. The results showed higher rates of internalizing symptoms in the clinical group. In addition, patients showed less interest in hobbies, less adherence to social organizations, impairment in social activities, and commitment to school performance compared to the control group. There was a positive correlation between the mothers' symptoms and each of the following PIC-2 domains: somatic concern (p < 0.01) and psychological discomfort (p < 0.01). In conclusion, youths with AD showed a withdrawn and reserved personality profile, involving distrust of impulses and avoidance of interactions with peers. Furthermore, psychoemotional problems of mothers adversely influenced the perception followed by anxiety and adjustment characteristics. More studies are needed to assess the maternal personality in youths with anxiety.

Reliability of parental reporting of child snoring in children referred for obstructive sleep apnea

Despite the high number of studies based on subjective reports of snoring, self-reported snoring has hardly been validated at all. As there is no "gold-standard" for objective snoring measurements, studies must evaluate whether the presence of snoring based on parental judgement is linked to objective measurements of nasal and/or pharyngeal obstruction in children referred for obstructive sleep apnea. A total of 146 children (median age 11 years) underwent polysomnography (with snoring recording using nasal cannula signal), acoustic rhinometry and pharyngometry, while their parents filled out the Spruyt-Gozal questionnaire assessing both frequency and loudness of subjective snoring. Three categories were further differentiated (null, low and high) for both frequency and loudness. The apnea-hypopnea index was significantly different in the three groups for both frequency (p = 0.04) and loudness (p = 0.01) of subjective snoring. Children in the low or high groups (frequency or loudness), compared with those in the null group, experienced a decline in both pharyngeal (sitting and supine positions) and nasopharyngeal (supine position) volumes (frequency, pharynx sitting: p = 0.03; supine: 0.005 and nasopharynx: p = 0.002; loudness, p = 0.03; p = 0.007 and p = 0.03; three group comparisons). Objective snoring frequency during the night obtained with cannula was weakly related to loudness of subjective snoring but not to subjective snoring frequency during the week, and was biased by nasal obstruction. In conclusion, our study showed that parental assessment of snoring is related to a reduction in both pharyngeal and nasopharyngeal volumes in snorers, arguing for the adequacy of their evaluation of both snoring frequency and loudness.

Attention deficit hyperactivity disorder and restless leg syndrome across the lifespan: A systematic review and meta-analysis

This systematic review aims to assess the association between attention deficit hyperactivity disorder (ADHD) and restless legs syndrome (RLS) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Databases were searched for original articles that reported prevalence data on ADHD and RLS until January 24th, 2023. Two independent reviewers evaluated the quality of the articles using the National Institutes of Health assessment tool. Among the 208 articles identified between 1996 and 2022, 29 were included. In large general population studies, 2.6-15.3% of participants met the RLS criteria, of which 3.2-17.4% presented with ADHD. In the ADHD group, RLS symptoms ranged from 11 to 42.9% in children and 20-33.0% in adults. This suggests a strong co-occurrence between RLS and ADHD. A common characteristic of these conditions is sleep fragmentation, as discussed in the reviewed papers. Although large-scale studies with comparable diagnostic criteria across the lifespan are required, our findings may advocate a possible common physiological pathway, including sleep fragmentation and dopaminergic system impairment.

Development and validation of moderate to severe obstructive sleep apnea screening test (ColTon) in a pediatric population

OBJECTIVE

Development and validation of a machine learning algorithm to predict moderate to severe obstructive sleep apnea syndrome (OSAS) in otherwise healthy children.

DESIGN

Multivariable logistic regression and cforest algorithm of a large cross-sectional data set of children with sleep-disordered breathing.

SETTING

An university pediatric sleep centre.

PARTICIPANTS

Children underwent clinical examination, acoustic rhinometry and pharyngometry, and surveying through parental sleep questionnaires, allowing the recording of 14 predictors that have been associated with OSAS. The dataset was nonrandomly split into a training (development) versus test (external validation) set (2:1 ratio) based on the time of the polysomnography. We followed the TRIPOD checklist.

RESULTS

We included 336 children in the analysis: 220 in the training set (median age [25th-75th percentile]: 10.6 years [7.4; 13.5], z-score of BMI: 1.96 [0.73; 2.50], 89 girls) and 116 in the test set (10.3 years [7.8; 13.0], z-score of BMI: 1.89 [0.61; 2.46], 51 girls). The prevalence of moderate to severe OSAS was 106/336 (32%). A machine learning algorithm using the cforest with pharyngeal collapsibility (pharyngeal volume reduction from sitting to supine position measured by pharyngometry) and tonsillar hypertrophy (Brodsky scale), constituting the ColTon index, as predictors yielded an area under the curve of 0.89, 95% confidence interval [0.85-0.93]. The ColTon index had an accuracy of 76%, sensitivity of 63%, specificity of 81%, negative predictive value of 84%, and positive predictive value of 59% on the validation set.

CONCLUSION

A cforest classifier allows valid predictions for moderate to severe OSAS in mostly obese, otherwise healthy children.

An investigation of the sleep macrostructure of girls with Rett syndrome

OBJECTIVE/BACKGROUND

Methyl-CpG-binding protein 2 (MeCP2) is of utmost importance in neuronal function. We aim to characterize phenotypic traits in the sleep of individuals with Rett Syndrome (RTT, OMIM # 312750), a rare disorder predominantly caused by mutations of the MECP2 gene.

PATIENTS/METHODS

An overnight polysomnographic recording was performed. Outcomes investigated were parameters of nocturnal sleep macrostructure, and sample stratification per genetic and clinical characteristics, and six key features of clinical severity was applied.

RESULTS

The sleep of our 21 RTT female subjects with a mutant MECP2 gene, aged 8.8 ± 5.4 years, showed no significant differences within strata. However, compared to a normative dataset, we found longer duration of wake time after sleep onset and total sleep time (TST) but shorter sleep onset latency, in RTT. Regarding the proportion of sleep stages per TST, higher stage N3 (%) with lower stage N2 (%) and REM (%) were generally seen. Such abnormalities became more uniformly expressed at the severe level of clinical features, particularly for hand functioning and walking.

CONCLUSIONS

RTT girls with MECP2 mutations in our study demonstrated an increased deep sleep and reduced rapid eye movement sleep proportion, which is mostly allied with their hand dysfunction severity. Poor sleep-on/off switching in RTT since embryogenesis is possibly linked to (psycho)motor impairment in the cases with MECP2 mutations.

Assessing Measurement Properties of a Simplified Chinese Version of Sleep Condition Indicator (SCI-SC) in Community Residents

Background: The study aimed to assess the measurement properties of a simplified Chinese version of the Sleep Condition Indicator (SCI-SC) in the community. Methods: A psychometric evaluation through an observational cross-sectional survey design was conducted. Community residents (N = 751) in Hangzhou, China completed the SCI-SC and the simplified Chinese version of the Sleep Quality Questionnaire (SQQ) in July 2021. Data were randomly split into a development sample (N = 375) for model development by exploratory factor analysis (EFA) and a holdout sample (N = 376) for validation by confirmatory factor analysis (CFA). Multi-group CFA (MGCFA) was used to assess configural, metric, scalar, and strict measurement invariance across gender, age, marital status, body mass index (BMI), napping habits, generic exercise, hobby, and administered survey. Moreover, statistical analyses were performed to determine the reliability (alpha and omega) and construct validity of the instrument. Results: Both factor analyses showed a stable solution with two dimensions of Sleep Pattern and Sleep-Related Impact. Good structural validity, robust internal consistency, and construct validity with the SQQ were demonstrated. There was evidence of strict invariance across gender, BMI, napping habits, generic exercise, hobby, and administered survey subgroups, but only metric and scalar invariances were established across age and marital status groups, respectively. Conclusions: The SCI-SC demonstrated promising psychometric properties, with high SQQ concordance and consistent structure of the original version. The SCI-SC can be used by sleep researchers as well as healthcare professionals in various contexts in detecting risks for insomnia disorder in the community.

Sleep Respiratory Disturbances in Girls with Rett Syndrome

Individuals with Rett Syndrome (RTT), a rare neurodevelopmental disorder, present disordered breathing during wakefulness. Whilst findings on breathing during sleep are contradictory, the relation between sleep breathing and their clinical features, genetic characteristics, age, and sleep phase is rarely investigated, which is the objective of this study. Overnight polysomnography (PSG) was performed. Sleep macrostructure parameters were compared between the RTT subjects with and without sleep-disordered breathing (SDB). The association between the apnea-hypopnea index (AHI) with age at PSG was tested. Particularly for RTT subjects with SDB, the respiratory indexes in REM and NREM sleep were compared. Stratified analyses per clinical characteristics, genetic characteristics, and clinical features' severity were performed. Non-parametric statistics were applied. A sample of 11 female RTT subjects, aged 8.69 ± 5.29 years with ten confirmed with MECP2 mutations, were studied. The average AHI was 3.94 ± 1.19/h TST, of which eight (72.73%) had obstructive sleep apnea, i.e., six in 1/h TST ≤ AHI ≤ 5/h TST, and two in AHI > 5/h TST. The mean SpO₂% was 81.00 ± 35.15%. The AHI was not significantly correlated with their age at PSG (r_s = -0.15, p = 0.67). Sleep macrostructure in SDB-absent and SDB-present groups was not different. Respiratory indexes in those with obstructive sleep apnea showed no difference between REM and NREM sleep nor any of the strata. In our clinical sample, more than half of the RTT subjects with MECP2 mutations had obstructive sleep apnea in both NREM and REM sleep which was unrelated to their clinical features. Our results also indicated hypoxemia throughout nocturnal sleep in RTT. To conclude, our results suggest that disordered breathing during sleep is prevalently present in RTT as an independent clinical feature.

Rapid Eye Movement Sleep during Early Life: A Comprehensive Narrative Review

The ontogenetic sleep hypothesis suggested that rapid eye movement (REM) sleep is ontogenetically primitive. Namely, REM sleep plays an imperative role in the maturation of the central nervous system. In coincidence with a rapidly developing brain during the early period of life, a remarkably large amount of REM sleep has been identified in numerous behavioral and polysomnographic studies across species. The abundant REM sleep appears to serve to optimize a cerebral state suitable for homeostasis and inherent neuronal activities favorable to brain maturation, ranging from neuronal differentiation, migration, and myelination to synaptic formation and elimination. Progressively more studies in Mammalia have provided the underlying mechanisms involved in some REM sleep-related disorders (e.g., narcolepsy, autism, attention deficit hyperactivity disorder (ADHD)). We summarize the remarkable alterations of polysomnographic, behavioral, and physiological characteristics in humans and Mammalia. Through a comprehensive review, we offer a hybrid of animal and human findings, demonstrating that early-life REM sleep disturbances constitute a common feature of many neurodevelopmental disorders. Our review may assist and promote investigations of the underlying mechanisms, functions, and neurodevelopmental diseases involved in REM sleep during early life.

Exploring the role of the endogenous opiate system in the pathogenesis of anemia in an opiate receptor knock-out model of Restless Legs Syndrome

Restless Legs Syndrome (RLS) is characterized by bothersome leg discomfort accompanied by an urge to move to obtain relief and symptoms are worse at night and on lying down. There is at least partial and temporary relief with activity. It is also an opioid responsive disorder, often accompanied by iron deficiency with or without anemia, and inflammation may be a precipitating factor in some cases. We created two in-vivo opiate receptor knock out mouse models of RLS - a triple opiate receptor knock-out mouse and a mu opiate receptor knock-out mouse. Both sets of animals were restless during the sleep period as is also true of RLS. Both of our knockout models showed statistically significantly decreased Hemoglobin and Hematocrit indicating anemia and both models showed statistically significant decreases in serum iron suggestive of either iron deficiency anemia or inflammatory anemia. The rest of the hematologic studies were not consistent enough to determine which of these two types of anemia was present in either model. An additional experiment in normal wild type mice showed a statistically significant decrease in serum iron when an opiate receptor blocker was used. To our knowledge this is the first demonstration that deficiency of endogenous opioids might play a role in the production of anemia. Our hypothesis is that an intact endogenous opiate system is necessary for red cell homeostasis. The presence of opioid receptors both on red blood cells and on various immunologically based white blood cells suggest mechanisms by which deficiency in the endogenous opiate system could cause anemia of either the iron deficiency or inflammatory types. The administration of opioid agonists or antagonists to iron deficient cultures of red blood cell precursors is a next step in determining the role of the endogenous opiate system in the maintenance of red cell homeostasis and in the possible prevention of iron deficiency or inflammatory anemia where iron dysregulation is key.

A meta-review of standard polysomnography parameters in Rett Syndrome

Rett Syndrome (RTT, OMIM 312750), a unique rare neurodevelopmental disorder, mostly affects females and causes severe multi-disabilities including poor sleep. This meta-analysis systematically reviewed the polysomnographic (PSG) data of individuals with RTT on both sleep macrostructure and sleep respiratory indexes and compared them to literature normative values. Studies were collected from PubMed, Web of Science, PsycINFO, Ebsco, Scopus, and Cochrane Library till 26 April 2022. Across 13 included studies, the 134 selected RTT cases were mostly females being MECP2 (n = 41) and CDKL5 (n = 4) positive. They were further stratified by gene, age, and clinical features. Findings of comparison with literature normative values suggested shorter total sleep time (TST) and sleep onset latency (SOL), twice as long wake after sleep onset (WASO) with lower sleep efficiency (SEI) in RTT, as well as increased non-rapid eye movement stage 3 (stage N3) and decreased rapid eye movement sleep. Based on limited data per stratifications, we found in RTT cases <5 years old lower stage N3, and in RTT cases >5 years old less WASO and more WASO in the epileptic strata. However, meta-results generated from studies designed with comparison groups only showed lower stage N1 in RTT than in healthy comparison, together with similar SEI and stage N3 to primary snoring subjects. For sleep respiratory indexes, severe disordered sleep breathing was confirmed across roughly all RTT strata. We are the first study to meta-analyze PSG data of subjects with RTT, illustrating shorter TST and aberrant sleep staging in RTT that may vary with age or the presence of epilepsy. Severe nocturnal hypoxemia with apneic events was also demonstrated. More studies are needed to explore and elucidate the pathophysiological mechanisms of these sleep findings in the future.

Stereotaxic atlas of the infant rat brain at postnatal days 7–13

Recently, researchers have paid progressively more attention to the study of neural development in infant rats. However, due to the lack of complete intracerebral localization information, such as clear nuclear cluster boundaries, identified main brain structures, and reliable stereotaxic coordinates, it is difficult and restricted to apply technical neuroscience to infant rat’s brain. The present study was undertaken to refine the atlas of infant rats. As such, we established a stereotaxic atlas of the infant rat’s brain at postnatal days 7–13. Furthermore, dye calibration surgery was performed in P7–P13 infant rats by injecting Methylene blue, and sections were incubated in Nissl solutions. From the panoramic images of the brain sections, atlases were made. Our article has provided the appearance and measurements of P7–P13 Sprague–Dawley rat pups. Whereas the atlas contains a series of about 530 coronal brain section images from olfactory bulbs to the brainstem, a list of abbreviations of the main brain structures, and reliable stereotaxic coordinates, which were demonstrated by vertical and oblique injections with fluorescent dye DiI. The present findings demonstrated that our study of P7–P13 atlases has reasonable nucleus boundaries and accurate and good repeatability of stereotaxic coordinates, which can make up for the shortage of postnatal rat brain atlas currently in the field.

The Role of Mindfulness in Mitigating the Detrimental Effects of Harsh Parenting among Chinese Adolescents: Testing a Moderated Mediation Model in a Three-Wave Study

Based on the conservation of resources theory, this study aimed to investigate the mediating role of depressive symptoms and the moderating role of mindfulness in the association between harsh parenting and adolescent suicidal ideation in the Chinese cultural context. Using a three-wave (i.e., three months apart) data collection among 371 Chinese adolescents, this study found that depressive symptoms mediated the relationship between harsh parenting and adolescent suicidal ideation. Moreover, adolescent mindfulness mitigated the effects of harsh parenting on suicidal ideation, as well as the indirect effect of harsh parenting on suicidal ideation via depressive symptoms. The theoretical and practical implications are discussed.

0306 Normative Data of Cyclic Alternating Pattern across the Lifespan

Introduction

Cyclic alternating pattern (CAP) is a marker of sleep instability, and neuroplasticity. Slow wave sleep has been described as a stable period, and CAP can be a marker of funcional delta sleep. The aim of this review was to evaluate the normative data of CAP parameters according to the aging process in healthy subjects.

Methods

Two authors independently searched databases using PRISMA guidelines through a systematic review and meta-analysis. Subgroup analysis and tests for heterogeneity were conducted. Descriptive statistics were used for the analysis of CAP variables. Meta-analyses were performed by using Comprehensive Meta- Analysis software. Data extracted from tables provide

Results

We found the evolution of CAP rate across the lifespan. Squares and diamond represent the CAP mean while bars represent the CAP range between 95% CI values according to each age range. We analysed 168 healthy individuals by CAP analyses. Scoring of CAP can begin at 3 months of life, when K-complexes, delta bursts, or spindles can be recognized. Rate of CAP increased with age, mainly during the first 2 years of life, then decreased in adolescence, and increased in the elderly. The A1 CAP subtype and CAP rate were high in school-aged children during slow-wave sleep (SWS). Our meta-analysis registered the lowest CAP rate in infants younger than 2 years old and the highest in the elderly.

Conclusion

The normative data of CAP in NREM sleep can be connected with brain maturation.The CAP rate increased with age and sleep depth, especially during SWS. These data in sleep disorders can be a treatment goal. CAP may reflect neurodiversity of endophenotype and human cronobiotypes. Further studies about CAP subtypes are needed.

Support (If Any)

 

Literature Cases Summarized Based on Their Polysomnographic Findings in Rett Syndrome

Rett syndrome (RTT) is a severe and rare neurodevelopmental disorder affecting mostly girls. In RTT, an impaired sleep pattern is a supportive criterion for the diagnosis, yet little is known regarding the sleep structure and sleep respiratory events. Aiming to delineate sleep by aggregating RTT case (series) data from published polysomnographic studies, seventy-four RTT cases were collected from eleven studies up until 6 February 2022 (PROSPERO: CRD 42020198099). We compared the polysomnographic data within RTT stratifications and to a typically developing population. MECP2 cases demonstrated shortened total sleep time (TST) with increased stage N3 and decreased REM sleep. In cases with CDKL5 mutations, TST was longer and they spent more time in stage N1 but less in stage N3 than those cases affected by MECP2 mutations and a typically developing population. Sleep-disordered breathing was confirmed by the abnormal apnea/hypopnea index of 11.92 ± 23.67/h TST in these aggregated cases. No association of sleep structure with chronological age was found. In RTT, the sleep macrostructure of MECP2 versus CDKL5 cases showed differences, particularly regarding sleep stage N3. A severe REM sleep propensity reduction was found. Aberrant sleep cycling, possibly characterized by a poor REM ‘on switch’ and preponderance in slow and high-voltage sleep, is proposed.

The month of birth has a seasonal effect in Chinese patients with narcolepsy and cataplexy

STUDY OBJECTIVES

We assessed the yearly seasonal, environmental effects on birth pattern in Chinese patients later diagnosed with narcolepsy and cataplexy and explored if this effect persisted in patients with symptoms onset date before, following, and after the 2009 H1N1 pandemic.

METHODS

A total of 1,942 patients with birth data information and diagnosed narcolepsy with cataplexy were included in this study. The birth month and seasonal effect of 1,064 patients born from 1970 to 2000 were compared to controls (n = 2,028,714) from the general population. Furthermore, birth season effect in 1,373 patients with definite disease onset month were compared among patients with onset date before (n = 595), following (from January 2010 to December 2010) (n = 325), and after (n = 453) the H1N1 pandemic.

RESULTS

Patients with narcolepsy and cataplexy had a significantly different seasonality from the general population (P = .027). The monthly distribution of birth month yielded a peak in November (odds ratio = 1.23 [95% confidence interval, 1.01-1.49], P = .042) and a trough in April (odds ratio = 0.68 [95% confidence interval, 0.52-0.88], P = .004). No significant difference was observed in the birth month across patients with symptom onset dates before, following, and after the 2009 H1N1 pandemic (P = .603).

CONCLUSIONS

This finding across many years of seasonal effect in Chinese narcolepsy cataplexy supports a role for early-life environmental influences on disease development.

CITATION

Guo J, Xu L, Wang J, et al. The month of birth has a seasonal effect in Chinese patients with narcolepsy and cataplexy. J Clin Sleep Med. 2022;18(2):461-467.

Daily concordance between ecological stressors and sleep in young minority children during the pre-COVID-19 outbreak period

OBJECTIVE

As the COVID-19 pandemic brings widespread changes in families, the sociology of sleep becomes noticeable. Yet, the socio-contextual determinants of a biopsychosocial phenomenon as sleep are poorly investigated. We examine changes concomitantly occurring in the child's sleep per familial and community stressors.

METHODS

During the pre-COVID-19 outbreak period, in 24 minority children (5.4 ± 1.7 years old, 54.2% girls), sleep was objectively measured 24 h for two consecutive weeks, and this was repeated three times over the study period of three months. The caregiver filled out questionnaires surveying sociodemographic, community and family aspects.

RESULTS

Children went to bed at 22:26 and woke up at 07:04, with each a variability of about 50 min. Money and time were revealed as related key stressors to sleep. Five dimensions best fitted their association. In general, concurrent changes within the individual child indicate that mean sleep variables seem to relate to predominantly features of the stressors (explained variance of 34.7 to 56.7%), while variability of sleep tends to associate to situational aspects of the stressors (explained variance of 30.4 to 61.8%). Associations were best explained in terms of the 24 h dimension, particularly exposing sleep variability.

CONCLUSION

Individual variabilities in a child's sleep are associated with familial resources, such as caregiver's time to self, money and basic needs. Time spent in bed, a modifiable factor by society and shaper of sleep quantity and quality, plays a key role in stressor-sleep associations. Insights from biopsychosocial perspectives may be valuable for understanding COVID-19 sleep studies, and the development of (post-) COVID-19 sleep recommendations.

Social media for students' sleep health promotion - a health intervention report during COVID -19

The COVID-19 pandemic has affected sleep health. Students' sleep health is essential for the performance of neuro-cognitive processes, as well as mental and physical balance. We assume the COVID19 pandemic has modified some sleep habits by prompting environmental and social interaction changes. In this study we surveyed a sample of 300 Brazilian students, with internet access, resident in the Federal District. They completed a questionnaire over two weeks in March 2020, i.e. the second and third week of the social isolation policy enacted in the Federal District due to COVID19. Valid responses from students aged18-24 years were analyzed. The sample was mostly female; 76,3% reported somnolence during the day, 70,2% anxiety and 87,8% worse sleep associated with stress and/or anxiety, which indicated the variables for an educational health intervention design in this context. Further, 53.2% made no effort to avoid screens before sleeping; 73.9% to avoid using the bed for work or watching television and 83.1% to avoid consuming heavy foods before sleeping. We then created an Instagram profile, @comodormimos, which focused on the main sleep issues revealed by participants in the survey. Posts on the profile were based on sleep-related subjects: sleep processes, sleep hygiene practices for students; sleep stages, function and regulation; and sleep-wake circadian rhythms. The profile gained 307 followers, mostly women (61,7%), 18-24 years old. We concluded that the Covid-10 pandemic period increased harmful sleep behavior in students. Further studies are needed to understand the impact of the COVID-19 pandemic on student sleep health.

A systematic review and meta-analysis of the cyclic alternating pattern across the lifespan

BACKGROUND

Cyclic alternating pattern (CAP) is the electroencephalogram (EEG) pattern described as a marker of sleep instability and assessed by NREM transient episodes in sleep EEG. It has been associated with brain maturation. The aim of this review was to evaluate the normative data of CAP parameters according to the aging process in healthy subjects through a systematic review and meta-analysis.

METHODS

Two authors independently searched databases using PRISMA guidelines. Discrepancies were reconciled by a third reviewer. Subgroup analysis and tests for heterogeneity were conducted.

RESULTS

Of 286 studies, 10 submitted a total of 168 healthy individuals to CAP analysis. Scoring of CAP can begin at 3 months of life, when K-complexes, delta bursts, or spindles can be recognized. Rate of CAP increased with age, mainly during the first 2 years of life, then decreased in adolescence, and increased in the elderly. The A1 CAP subtype and CAP rate were high in school-aged children during slow-wave sleep (SWS). A1 CAP subtypes were significantly more numerous in adolescents compared with other groups, while the elderly showed the highest amounts of A2 and A3 CAP subtypes. Our meta-analysis registered the lowest CAP rate in infants younger than 2 years old and the highest in the elderly.

CONCLUSIONS

This review summarized the normative data of CAP in NREM sleep during the aging process. The CAP rate increased with age and sleep depth, especially during SWS. Parameters of CAP may reflect gender hormonal effects and neuroplasticity. More reports on CAP subtypes are needed for their reference values establishment.

Altered Sleep-Related Consolidation and Neurocognitive Comorbidity in CECTS

Our aim is to use neurophysiological sleep-related consolidation (SRC) phenomena to identify putative pathophysiological mechanisms in CECTS linked to diffuse neurocognitive deficits. We argue that there are numerous studies on the association between seizure aspects and neurocognitive functioning but not as many on interictal variables and neurocognitive deficits. We suggest two additional foci. First, the interictal presentation in CECTS and second, neuronal oscillations involved in SRC processes. Existing data on mechanisms through which interictal epileptiform spikes (IES) impact upon SRC indicate that they have the potential to: (a) perturb cross-regional coupling of neuronal oscillations, (b) mimic consolidation processes, (c) alter the precision of the spatiotemporal coupling of oscillations, and (d) variably impact upon SRC performance. Sleep spindles merit systematic study in CECTS in order to clarify: (a) the state of the slow oscillations (SOs) with which they coordinate, (b) the precision of slow oscillation-spindle coupling, and (c) whether their developmental trajectories differ from those of healthy children. We subsequently review studies on the associations between IES load during NREM sleep and SRC performance in childhood epilepsy. We then use sleep consolidation neurophysiological processes and their interplay with IES to help clarify the diffuse neurocognitive deficits that have been empirically documented in CECTS. We claim that studying SRC in CECTS will help to clarify pathophysiological mechanisms toward diverse neurocognitive deficits. Future developments could include close links between the fields of epilepsy and sleep, as well as new therapeutic neurostimulation targets. At the clinical level, children diagnosed with CECTS could benefit from close monitoring with respect to epilepsy, sleep and neurocognitive functions.

Restless Legs Syndrome Shows Increased Silent Postmortem Cerebral Microvascular Disease With Gliosis

Background

Patients with restless legs syndrome (RLS) have increased silent microvascular disease by magnetic resonance imaging. However, there has been no previous autopsy confirmation of these magnetic resonance imaging findings. RLS is also frequently associated with inflammatory and immunologically mediated medical disorders. The postmortem cortex in patients with RLS was therefore evaluated for evidence of microvascular and immunological changes.

Methods and Results

Ten microvascular injury samples of precentral gyrus in 5 patients with RLS (3 men, 2 women; mean age, 81 years) and 9 controls (2 men, 7 women; mean age, 90 years) were studied by hematoxylin and eosin stains in a blinded fashion. None of the subjects had a history of stroke or neurologic insults. In a similar manner, the following immunohistochemistry stains were performed: (1) glial fibrillary acidic protein (representing gliosis, reactive change of glial cells in response to damage); (2) CD3 (a T‐cell marker); (3) CD19 (a B‐cell marker); (4) CD68 (a macrophage marker); and (5) CD117 (a mast cell marker). Patients with RLS had significantly greater silent microvascular disease (P=0.015) and gliosis (P=0.003). T cells were increased in RLS compared with controls (P=0.009) and tended to colocalize with microvascular disease (P=0.003). Other markers did not differ. There was no correlation between microvascular lesion load and RLS severity or duration.

Conclusions

Patients with RLS had statistically significantly more silent cerebral microvascular disease and gliosis than controls compatible with previous magnetic resonance imaging studies and with studies showing a link between RLS and hypertension, clinical stroke, and cardiovascular disease. T‐cell invasion may be a secondary phenomenon.

Combined effects of weight change trajectories and eating behaviors on childhood adiposity status: A birth cohort study

Previous studies have suggested that infant rapid weight change can be associated with an increased weight later in life. However, the weight change trajectory in early life over time and which childhood lifestyle behaviors may modify the risk of rapid weight change have not been characterized. Using our ongoing birth cohort study, we have addressed these issues. Nine follow-up time points (birth, 3, 6, 9, 12, 18, 24, 36, and 48 months) were used to calculate the change between two adjacent weight-for-age z-scores (WAZ-change), and then WAZ-change trajectories were defined via group-based trajectory modeling. The solitary, independent and combined effects of WAZ-change trajectories and each lifestyle factor (eating behaviors, physical activity, media exposure time and total sleep duration) on childhood adiposity measures at age 4 years were determined using multivariate regression analysis. Overall, 84 (38%) children had a steady growth trajectory from birth to 4 years, while the other 137 (62%) children had an early infancy rapid growth trajectory, particularly in the first three months. Compared to children with steady growth, children with early infancy rapid growth had a significantly higher body mass index, waist circumference, and subcutaneous fat. Moreover, weight change trajectory and three eating behaviors (i.e. food responsiveness, satiety responsiveness and food fussiness), not only had independent effects, but also combined (synergistic) effects on the majority of adiposity measures. Our results extend the current literature and provide a potentially valuable model to aid clinicians and health professionals in designing early-life interventions targeting specific populations, specific ages and specific lifestyle behaviors to prevent childhood overweight/obesity.

Reliability and validity of the Chinese version of Narcolepsy Severity Scale in adult patients with narcolepsy type 1

OBJECTIVE

To evaluate reliability and validity of the Chinese version of Narcolepsy Severity Scale (NSS) in adult patients with narcolepsy type 1 (NT1).

METHODS

One hundred and fifty-one adult patients (≥18 years) with NT1 were recruited. All filled out the 15-item Chinese version of NSS. Item analysis included critical ratio and correlation analysis. The validity of NSS was assessed by exploratory factor analysis, discriminant validity and convergent validity. Reliability of NSS was assessed by Cronbach's α coefficient, spilt-half reliability and test-retest reliability.

RESULTS

Critical value of all 15 items ranged from 3.01 to 13.36. Each item was significantly correlated with the total score by a correlation coefficient (r) ranging from 0.219 to 0.700. Three common domains were extracted and 15 items explained 54.86% of the total variance. There was a shift in domains compared to the English version likely due to cultural differences. Cronbach's α coefficient for the total scale of 15 items was 0.821 and for three factors was 0.726, 0.748 and 0.760 respectively. The NSS had good correlation with Epworth sleepiness scale scores, Insomnia severity index scores and moderate correlation with mean the sleep latency of polysomnographic recording, and European Quality of Life-5 Dimensions Questionnaire. The Chinese version of NSS showed good spilt-half reliability and test-retest reliability.

CONCLUSION

The Chinese version of NSS shows satisfactory psychometric properties with good validity and reliability. It is applicable to evaluate the severity and consequences of symptoms in Chinese adult patients with NT1.

Changes in sleep patterns and disturbances in children and adolescents in Italy during the Covid-19 outbreak

Objective

To examine the impact of home confinement during the COVID-19 pandemic on the sleep patterns and sleep disturbances in Italian children and adolescents.

Methods

Participants completed an anonymous online survey, shared via social media and targeting children and adolescents aged 1–18 years, subdivided into age groups: 1–3, 4–5, 6–12, and 13–18 years. Caregivers completed a modified version of the Sleep Disturbance Scale for Children (SDSC), along with demographic information.

Results

The final sample consisted of 4314 subjects: 2217 males (50.4%) and 2097 females (49.6%). Age group distribution was: 1–3 years 1263 (29.3%), 4–5 years 893 (20.7%), 6–12 years 1848 (42.8%) and 13–18 years 310 (7.2%). We found a significant delay in bedtime and risetime in all age groups. School-age children and adolescents experienced the most significant delay: weekday bedtime ≥23 was reported by 28.4% of 6- to 12-year-old children during lockdown vs. 0.9% before and by 63.5% vs. 12.3% of 13- to 18-year-old adolescents. Risetime was also delayed with most subjects waking up after 8 in all age groups and sleep duration increased in all groups but not in the younger group. The screen time (excluding online lessons) boosted during the lockdown, mainly in older children but also in younger children. Sleep disorders increased in all groups but not in adolescents. Younger groups had an increased prevalence of difficulty falling asleep, anxiety at bedtime, night awakenings, nightmares and sleep terrors.

Conclusion

Our study demonstrates that confinement due to COVID-19 determined a big delay in sleep/wake schedule of children in all age groups as well as an increase of sleep disturbances in all groups but adolescents.

Fidgety Philip and the Suggested Clinical Immobilization Test: Annotation data for developing a machine learning algorithm

The cartoon Fidgety Philip, the banner of Western-ADHD diagnosis, depicts a 'restless' child exhibiting hyperactive-behaviors with hyper-arousability and/or hypermotor-restlessness (H-behaviors) during sitting. To overcome the gaps between differential diagnostic considerations and modern computing methodologies, we have developed a non-interpretative, neutral pictogram-guided phenotyping language (PG-PL) for describing body-segment movements during sitting (Journal of Psychiatric Research). To develop the PG-PL, seven research assistants annotated three original Fidgety Philip cartoons. Their annotations were analyzed with descriptive statistics. To review the PG-PL's performance, the same seven research assistants annotated 12 snapshots with free hand annotations, followed by using the PG-PL, each time in randomized sequence and on two separate occasions. After achieving satisfactory inter-observer agreements, the PG-PL annotation software was used for reviewing videos where the same seven research assistants annotated 12 one-minute long video clips. The video clip annotations were finally used to develop a machine learning algorithm for automated movement detection (Journal of Psychiatric Research). These data together demonstrate the value of the PG-PL for manually annotating human movement patterns. Researchers are able to reuse the data and the first version of the machine learning algorithm to further develop and refine the algorithm for differentiating movement patterns.

Neurocognitive Effects of Sleep Disruption in Children and Adolescents

A main childhood task is learning. In this task, the role of sleep is increasingly demonstrated. Although most literature examining this role focuses on preadolescence and middle adolescence, some studies apply napping designs in preschoolers. Studies overall conclude that without proper sleep a child's cognitive abilities suffer, but questions on how and to what extent linger. Observational studies show the hazards of potential confounders such as an individual's resilience to poor sleep as well as developmental risk factors (eg, disorders, stressors). A better understanding of cognitive sleep neuroscience may have a big impact on pediatric sleep research and clinical applications.

Restless sleep in children: A systematic review

This systematic review assessed the prevalence of restless sleep in children, documented the association of restless sleep with other conditions, and summarized the existing evidence regarding whether restless sleep should be considered a distinct sleep disorder. A comprehensive search of electronic databases was performed using the broad search term "restless sleep" in all fields. Of the 266 articles retrieved, 107 were retained for inclusion in this review. The majority (n = 93) were observational studies. The studies were grouped under several pathologic/condition categories: sleep-disordered breathing (n = 19); adenotonsillectomy (n = 7); respiratory disorders, otitis media, and smoke exposure (n = 12); sleep-related movement disorders and restless sleep disorder (n = 11); neurologic or psychiatric disorders (n = 7); Down syndrome/other neurodevelopmental disorders (n = 10); sleep-related bruxism and other sleep disorders (n = 7); and restless sleep in the general population/mixed clinical samples (n = 18). A high prevalence of restless sleep was found in children with many of these underlying conditions, likely related to associated inherent sleep disruption and frequent awakenings (e.g., apnea and periodic limb movements), pain, sleep instability, and caregiver perception. The majority of studies identified restless sleep as reported by the caregiver, only 34 studies attempted to define restless sleep further. Four studies provided supportive evidence for designating restless sleep as an independent sleep disorder, restless sleep disorder (RSD). This review highlights the fact that the prevalence, etiology and sequelae (including daytime impairments) of restless sleep in children are important topics deserving of further research and that clinical definitions based on empirical evidence need to be developed. The designation of "primary" versus "secondary" restless sleep may be a useful construct, especially with regard to developing clinical trials and treatment algorithms.

Is Fidgety Philip's ground truth also ours? The creation and application of a machine learning algorithm

BACKGROUND

Behavioral observations support clinical in-depth phenotyping but phenotyping and pattern recognition are affected by training background. As Attention Deficit Hyperactivity Disorder, Restless Legs syndrome/Willis Ekbom disease and medication induced activation syndromes (including increased irritability and/or akathisia), present with hyperactive-behaviors with hyper-arousability and/or hypermotor-restlessness (H-behaviors), we first developed a non-interpretative, neutral pictogram-guided phenotyping language (PG-PL) for describing body-segment movements during sitting.

METHODOLOGY & RESULTS

The PG-PL was applied for annotating 12 1-min sitting-videos (inter-observer agreements >85%->97%) and these manual annotations were used as a ground truth to develop an automated algorithm using OpenPose, which locates skeletal landmarks in 2D video. We evaluated the algorithm's performance against the ground truth by computing the area under the receiver operator curve (>0.79 for the legs, arms, and feet, but 0.65 for the head). While our pixel displacement algorithm performed well for the legs, arms, and feet, it predicted head motion less well, indicating the need for further investigations.

CONCLUSION

This first automated analysis algorithm allows to start the discussion about distinct phenotypical characteristics of H-behaviors during structured behavioral observations and may support differential diagnostic considerations via in-depth phenotyping of sitting behaviors and, in consequence, of better treatment concepts.

Narcolepsy Presentation in Diverse Populations: an Update

Purpose of Review

We performed a literature search to generate incidence and prevalence rates of narcolepsy in diverse populations based on current available data.

Recent Findings

With an onset in childhood, narcolepsy often has a delayed diagnosis due to symptoms of excessive daytime sleepiness not being recognized or being misdiagnosed. Clinical, electrophysiological, and biological tests are needed in order to diagnose narcolepsy. At the same time, the discovery of the link with the immunoregulatory human leukocyte antigen complex and the adverse events in relation to the H1N1 pandemic vaccines have shuffled the epidemiological numbers.

Summary

In this meta-review, we pooled incidence rates and prevalence rates reported in 30 countries or from 209 sets of data. Findings are reported per age, continent, and proxy race/ethnicity as well as period (i.e., before/after the pandemic). This meta-review showed that narcolepsy occurs in 0.87–1.21 of the world population, with specifically NT1 being investigated. Its pooled incidence rate in vaccinated samples is 1.58. There is furthermore an underreporting of narcolepsy in ethnic/race and gender minorities, of childhood narcolepsy type 2 and potential comorbid conditions masking the clinical complaints and hence timely diagnosis.